Strong winds and periods of moderate to heavy snowfall developed over the north central mountains of Colorado. Storm totals included: 13 inches at Summit Ranch, 11 inches at Berthoud and Loveland SNOTELS; 10 inches at Jackwacker Gulch SNOTEL, 8 inches at Middle Fork Camp SNOTEL, with lesser amounts of 3 to 6 inches elsewhere.
Every event with a place to put it; 3 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS BOU wrote it up.
Strong winds and periods of moderate to heavy snowfall developed over the north central mountains of Colorado. Storm totals included: 13 inches at Summit Ranch, 11 inches at Berthoud and Loveland SNOTELS; 10 inches at Jackwacker Gulch SNOTEL, 8 inches at Middle Fork Camp SNOTEL, with lesser amounts of 3 to 6 inches elsewhere. A peak wind gust to 76 mph was recorded atop Berthoud Pass. Elsewhere, peak wind gusts above timberline generally ranged from 55-65 mph.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Denver/Boulder, CO wrote its last area forecast discussion before the first event at Feb 5, 4:50 AM MST, 10 minutes earlier.
Area Forecast Discussion National Weather Service Denver/Boulder CO 450 AM MST Mon Feb 5 2018 .SHORT TERM...(Today and tonight) Issued at 450 AM MST Mon Feb 5 2018 Moderate northwesterly flow aloft continues with another batch of moisture expected to move into the mountains today which will produce snow into tonight. An upper level jet will be overhead this afternoon and evening, which will help precipitation to spread out onto the plains this evening. A cold front is also expected to move over the plains late this afternoon with upslope easterly winds developing behind it. The airmass over the plains is expected to reach saturation during the evening with the snow developing after that. With the jet overhead, banded snowfall will be possible which could lead to more snowfall than the latest models would have us believe. For now, will mention 1 to 2 inch accumulations across the plains tonight. In the mountains, snow has already developed according to web cameras and radar data. Light to moderate snow should continue all day as moisture aloft continues moving into the region. A Winter Weather Advisory will go into effect at 5 AM which will continue through today and tonight. Snow accumulations of 4 to 10 inches with locally higher amounts can be expected. .LONG TERM...(Tuesday through Sunday) Issued at 450 AM MST Mon Feb 5 2018 n upper level trough embedded in NW flow aloft will move across the area on Tue. This feature combined with favorable orographics will continue to produce periods of light snow in the mountains thru the day. Over nern CO there could be some lingering light snow in the morning hours mainly over the far ern plains. As for highs readings will range from the lower 30s over the far nern plains with lower to mid 40's closer to the foothills. For Wed into Thu the flow aloft will be mainly WNW with only some higher moisture embedded in the flow. Thus will not mention any pcpn across the area. At the sfc, a lee trough will develop along the front range on Wed and then strengthen on Thu. As a result should see a gradual warming trend across nern CO with readings in the 50s to around 60 by Thu. By Fri WNW flow aloft will increase across the area with cross-sections still showing moisture confined to the mid to upper levels. Meanwhile there are substantial differences between the ECMWF and GFS regarding another cold front affecting the plains. The ECMWF has this fnt moving across nern CO by midday while the GFS keeps the fnt further north thru the aftn. As a result the GFS has highs in the upper 50s to mid 60s over nern CO while the ECMWF has readings at least 20 degrees colder. For now will go with a blended solution until it becomes more obvious what will occur. For Fri night into Sat the GFS has a strong upper level trough moving into the area fm the NW while the ECMWF has a much weaker system. Naturally the GFS solution would lead to a good chc of snow along with colder temperatures across the area. The ECMWF solution would also have colder temperatures but only some light pcpn. For now will just keep in a chc of snow for Fri night into Sat along with colder temps. && .AVIATION...(For the 12Z TAFS through 12Z Tuesday morning) Issued at 450 AM MST Mon Feb 5 2018 Minimal aviation impacts through today, other than gusty winds at times out of the west and northwest. Later this afternoon a cold front will move through, shifting winds to the north and then east. The airmass will moisten after the cold front moves through and easterly winds will help produce lower level clouds. IFR conditions are expected to develop with rain showers changing over to snow by 7 PM or 8 PM. An inch or two of snow accumulation will be possible overnight. && .BOU WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until 5 AM MST Tuesday for COZ031-033- 034. && SHORT TERM...Dankers LONG TERM...RPK AVIATION...Dankers
Hazardous Weather Outlook National Weather Service Denver/Boulder CO 1044 AM MST Sun Feb 4 2018 COZ030>051-051745- Jackson County Below 9000 Feet- West Jackson and West Grand Counties Above 9000 Feet- Grand and Summit Counties Below 9000 Feet- South and East Jackson/Larimer/North and Northeast Grand/ Northwest Boulder Counties Above 9000 Feet- South and Southeast Grand/West Central and Southwest Boulder/ Gilpin/Clear Creek/Summit/North and West Park Counties Above 9000 Feet-Larimer and Boulder Counties Between 6000 and 9000 Feet- Jefferson and West Douglas Counties Above 6000 Feet/Gilpin/Clear Creek/Northeast Park Counties Below 9000 Feet- Central and Southeast Park County- Larimer County Below 6000 Feet/Northwest Weld County- Boulder And Jefferson Counties Below 6000 Feet/West Broomfield County- North Douglas County Below 6000 Feet/Denver/West Adams and Arapahoe Counties/East Broomfield County- Elbert/Central and East Douglas Counties Above 6000 Feet- Northeast Weld County-Central and South Weld County-Morgan County- Central and East Adams and Arapahoe Counties- North and Northeast Elbert County Below 6000 Feet/North Lincoln County- Southeast Elbert County Below 6000 Feet/South Lincoln County- Logan County-Washington County-Sedgwick County-Phillips County- 1044 AM MST Sun Feb 4 2018 This hazardous weather outlook is for northeast and north central Colorado. .DAY ONE...Today and Tonight Light snow will linger mainly along the higher west facing slopes today, with little additional accumulation expected. Gusty winds above timberline however will produce areas of blowing snow and reduced visibilities. West winds 25 to 35 mph will occur with gusts up to 60 mph above timberline. Be prepared for winter travel and slick road conditions across the mountains. Across the northeast Colorado plains, a cold front has brought a shallow and moist airmass into the region. Areas of light snow and patchy fog will diminish this afternoon. Improving visibilities are expected later today with skies becoming partly cloudy. Temperatures will remain chilly. Motorists are reminded to reduce speeds while driving and watch out for icy surfaces, especially on bridges and overpasses. .DAYS TWO THROUGH SEVEN...Monday through Saturday Snow will increase in the mountains on Monday as another cold front moves across northeast Colorado in the afternoon. A weather system will move across the area Monday night into early Tuesday. This will bring more snow to the mountains with a good chance of rain changing to snow across the plains Monday evening. The snow may linger into Tuesday morning before ending by midday. Warmer and drier weather is expected across the area Wednesday and Thursday, with another chance for colder weather and snow by Friday. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed today or tonight. Cooper/Gimmestad
The national radar mosaic for the moment the first event began.
3 winter weather. Local standard time, as filed.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2018Every state in 2018This day in weather historyWarnings in Colorado, February 2018
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 739881, 739882, 739883.